Socio-economic inequalities in childhood stunting among children under five years in South Africa and Lesotho

Stunting remains high in South Africa and Lesotho despite programmes and interventions designed to improve children’s nutritional outcomes. Minimal research exists on the magnitude and determinants of socio-economic inequalities causing child stunting in South Africa and Lesotho. This study took the form of a retrospective analysis, utilising cross-sectional data from the 2016 South African Demographic and Health Survey (SADHS) and 2023 Lesotho Demographic and Health Survey (LDHS) to examine socio-economic inequalities in stunting among children under five years. The 2016 SADHS and 2023 LDHS captured samples of 1468 and 1574 children respectively. Stunting was defined using the WHO child growth standards. Data were analysed at four levels using descriptive, bivariate, concentration curves and multivariable decomposition analysis. Socio-economic-related inequalities were quantified using the Erreygers corrected concentration index (CCI), and decomposition analysis was conducted to identify the main contributors to inequality. The prevalence of stunting in children under five years in Lesotho was 35.6% (95% CI 32.6–38.7) while in South Africa the prevalence rate was 27.4% (95% CI 24.3–30.7). The overall concentration index was negative and statistically significant in both South Africa (CCI = − 0.1442, p < 0.001) and in Lesotho (CCI = − 0.1818, p < 0.001) indicating pro-poor inequality, where stunting was more prevalent among children from poorer households. In South Africa, stunted children tended to be located more often in rural areas compared to urban areas (Erreygers coefficient = 0.1015, p < 0.05). The results underscore the importance of interventions aimed at enhancing mothers’ educational attainment, household wealth, and rural disadvantage in order to reduce inequities in childhood nutrition. Strengthening integrated nutrition and social protection policies is critical to achieving equitable improvements in child nutritional outcomes in the study countries.